ospf6d: track explicit interface type config

If the interface doesn't exist in system, we'll default to broadcast and
then later not change that when the interface comes up.  Explicitly
track whether the user configured the type and properly auto-set it if
they didn't.

Fixes: #3930
Fixes: #4873
Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

ospf6d/ospf6_interface.c

@@ -681,6 +681,9 @@ int interface_up(struct thread *thread)
 	oi = (struct ospf6_interface *)THREAD_ARG(thread);
 	assert(oi && oi->interface);
 
+	if (!oi->type_cfg)
+		oi->type = ospf6_default_iftype(oi->interface);
+
 	/*
 	 * Remove old pointer. If this thread wasn't a timer this
 	 * operation won't make a difference, because it is already NULL.
@@ -877,6 +880,19 @@ int interface_down(struct thread *thread)
 }
 
 
+static const char *ospf6_iftype_str(uint8_t iftype)
+{
+	switch (iftype) {
+	case OSPF_IFTYPE_LOOPBACK:
+		return "LOOPBACK";
+	case OSPF_IFTYPE_BROADCAST:
+		return "BROADCAST";
+	case OSPF_IFTYPE_POINTOPOINT:
+		return "POINTOPOINT";
+	}
+	return "UNKNOWN";
+}
+
 /* show specified interface structure */
 static int ospf6_interface_show(struct vty *vty, struct interface *ifp)
 {
@@ -885,23 +901,16 @@ static int ospf6_interface_show(struct vty *vty, struct interface *ifp)
 	struct prefix *p;
 	struct listnode *i;
 	char strbuf[PREFIX2STR_BUFFER], drouter[32], bdrouter[32];
-	const char *type;
+	uint8_t default_iftype;
 	struct timeval res, now;
 	char duration[32];
 	struct ospf6_lsa *lsa;
 
-	/* check physical interface type */
-	if (if_is_loopback(ifp))
-		type = "LOOPBACK";
-	else if (if_is_broadcast(ifp))
-		type = "BROADCAST";
-	else if (if_is_pointopoint(ifp))
-		type = "POINTOPOINT";
-	else
-		type = "UNKNOWN";
+	default_iftype = ospf6_default_iftype(ifp);
 
 	vty_out(vty, "%s is %s, type %s\n", ifp->name,
-		(if_is_operative(ifp) ? "up" : "down"), type);
+		(if_is_operative(ifp) ? "up" : "down"),
+		ospf6_iftype_str(default_iftype));
 	vty_out(vty, "  Interface ID: %d\n", ifp->ifindex);
 
 	if (ifp->info == NULL) {
@@ -910,6 +919,10 @@ static int ospf6_interface_show(struct vty *vty, struct interface *ifp)
 	} else
 		oi = (struct ospf6_interface *)ifp->info;
 
+	if (if_is_operative(ifp) && oi->type != default_iftype)
+		vty_out(vty, "  Operating as type %s\n",
+			ospf6_iftype_str(oi->type));
+
 	vty_out(vty, "  Internet Address:\n");
 
 	for (ALL_LIST_ELEMENTS_RO(ifp->connected, i, c)) {
@@ -1806,6 +1819,8 @@ DEFUN (ipv6_ospf6_network,
 	}
 	assert(oi);
 
+	oi->type_cfg = true;
+
 	if (strncmp(argv[idx_network]->arg, "b", 1) == 0) {
 		if (oi->type == OSPF_IFTYPE_BROADCAST)
 			return CMD_SUCCESS;
@@ -1846,6 +1861,8 @@ DEFUN (no_ipv6_ospf6_network,
 		return CMD_SUCCESS;
 	}
 
+	oi->type_cfg = false;
+
 	type = ospf6_default_iftype(ifp);
 	if (oi->type == type) {
 		return CMD_SUCCESS;
@@ -1913,13 +1930,10 @@ static int config_write_ospf6_interface(struct vty *vty)
 		if (oi->mtu_ignore)
 			vty_out(vty, " ipv6 ospf6 mtu-ignore\n");
 
-		if (oi->type != ospf6_default_iftype(ifp)) {
-			if (oi->type == OSPF_IFTYPE_POINTOPOINT)
-				vty_out(vty,
-					" ipv6 ospf6 network point-to-point\n");
-			else if (oi->type == OSPF_IFTYPE_BROADCAST)
-				vty_out(vty, " ipv6 ospf6 network broadcast\n");
-		}
+		if (oi->type_cfg && oi->type == OSPF_IFTYPE_POINTOPOINT)
+			vty_out(vty, " ipv6 ospf6 network point-to-point\n");
+		else if (oi->type_cfg && oi->type == OSPF_IFTYPE_BROADCAST)
+			vty_out(vty, " ipv6 ospf6 network broadcast\n");
 
 		ospf6_bfd_write_config(vty, oi);
 

ospf6d/ospf6_interface.h

@@ -55,6 +55,7 @@ struct ospf6_interface {
 
 	/* Network Type */
 	uint8_t type;
+	bool type_cfg;
 
 	/* Router Priority */
 	uint8_t priority;